[PATCH] fix CRC16 misnaming

As pointed by Thomas Sailer, crc16.c module contains CRC16-CCITT (x^16 + x^12
+ x^5 + 1) implementation, not IBM CRC16 (x^16 + x^15 + x^2 + 1) one.  Looks
like we need to rename it accordingly and this patchset does exactly this.
Signed-off-by: Andrey Panin <pazke@donpac.ru>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

include/linux/crc-ccitt.h

+#ifndef _LINUX_CRC_CCITT_H
+#define _LINUX_CRC_CCITT_H
+
+#include <linux/types.h>
+
+extern u16 const crc_ccitt_table[256];
+
+extern u16 crc_ccitt(u16 crc, const u8 *buffer, size_t len);
+
+static inline u16 crc_ccitt_byte(u16 crc, const u8 c)
+{
+	return (crc >> 8) ^ crc_ccitt_table[(crc ^ c) & 0xff];
+}
+
+#endif /* _LINUX_CRC_CCITT_H */

include/linux/crc16.h

-#ifndef _LINUX_CRC16_H
-#define _LINUX_CRC16_H
-
-#include <linux/types.h>
-
-extern u16 const crc16_table[256];
-
-extern u16 crc16(u16 crc, const u8 *buffer, size_t len);
-
-static inline u16 crc16_byte(u16 crc, const u8 c)
-{
-	return (crc >> 8) ^ crc16_table[(crc ^ c) & 0xff];
-}
-
-#endif /* _LINUX_CRC16_H */

lib/Kconfig

@@ -4,13 +4,13 @@
 
 menu "Library routines"
 
-config CRC16
-	tristate "CRC16 functions"
+config CRC_CCITT
+	tristate "CRC-CCITT functions"
 	help
 	  This option is provided for the case where no in-kernel-tree
-	  modules require CRC16 functions, but a module built outside the
-	  kernel tree does. Such modules that use library CRC16 functions
-	  require M here.
+	  modules require CRC-CCITT functions, but a module built outside
+	  the kernel tree does. Such modules that use library CRC-CCITT
+	  functions require M here.
 
 config CRC32
 	tristate "CRC32 functions"

lib/Makefile

@@ -18,7 +18,7 @@ ifneq ($(CONFIG_HAVE_DEC_LOCK),y)
   lib-y += dec_and_lock.o
 endif
 
-obj-$(CONFIG_CRC16)	+= crc16.o
+obj-$(CONFIG_CRC_CCITT)	+= crc-ccitt.o
 obj-$(CONFIG_CRC32)	+= crc32.o
 obj-$(CONFIG_LIBCRC32C)	+= libcrc32c.o
 

lib/crc16.c → lib/crc-ccitt.c

 /*
- *	linux/lib/crc16.c
+ *	linux/lib/crc-ccitt.c
  *
  *	This source code is licensed under the GNU General Public License,
  *	Version 2. See the file COPYING for more details.
@@ -7,7 +7,7 @@
 
 #include <linux/types.h>
 #include <linux/module.h>
-#include <linux/crc16.h>
+#include <linux/crc-ccitt.h>
 
 /*
  * This mysterious table is just the CRC of each possible byte. It can be
@@ -15,7 +15,7 @@
  * be seen in entry 128, 0x8408. This corresponds to x^0 + x^5 + x^12.
  * Add the implicit x^16, and you have the standard CRC-CCITT.
  */
-u16 const crc16_table[256] = {
+u16 const crc_ccitt_table[256] = {
 	0x0000, 0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf,
 	0x8c48, 0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7,
 	0x1081, 0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e,
@@ -49,21 +49,21 @@ u16 const crc16_table[256] = {
 	0xf78f, 0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330,
 	0x7bc7, 0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
 };
-EXPORT_SYMBOL(crc16_table);
+EXPORT_SYMBOL(crc_ccitt_table);
 
 /**
- *	crc16 - recompute the CRC for the data buffer
+ *	crc_ccitt - recompute the CRC for the data buffer
  *	@crc - previous CRC value
  *	@buffer - data pointer
  *	@len - number of bytes in the buffer
  */
-u16 crc16(u16 crc, u8 const *buffer, size_t len)
+u16 crc_ccitt(u16 crc, u8 const *buffer, size_t len)
 {
 	while (len--)
-		crc = crc16_byte(crc, *buffer++);
+		crc = crc_ccitt_byte(crc, *buffer++);
 	return crc;
 }
-EXPORT_SYMBOL(crc16);
+EXPORT_SYMBOL(crc_ccitt);
 
-MODULE_DESCRIPTION("CRC16 calculations");
+MODULE_DESCRIPTION("CRC-CCITT calculations");
 MODULE_LICENSE("GPL");